With regard to a vehicular air conditioning unit, a refrigerant pipe of a refrigerating device is generally supported by a pipe joint in a form of flange. The pipe joint is fastened to the refrigerating device with bolts or screws. Specifically, a refrigerant passage is formed within the pipe joint. The pipe joint is fastened such that a first end of the refrigerant passage is connected to a refrigerant port of the refrigerating device and a second end of the refrigerant passage is connected to the end of the refrigerant pipe. After the pipe and the pipe joint are connected as above, the pipe and the pipe joint are integrally brazed.
According to the connecting structure and the method, the pipe joint has a complicated form and the connecting process takes time because of the brazing. To solve this disadvantage, a connecting method without brazing has been proposed. Such method is for example disclosed in JP-A-2000-46259 (U.S. Pat. No. 6,328,351 B1).
According to the method, as shown in FIG. 21, an end of a pipe 30 is first inserted into an opening 31a of a joint base member 31 through an insertion hole 32a of the flange member 32. Then, the end of the pipe 30 is pressed by a punch for enlarging an inside diameter of the end of the pipe 30. As a result, the inside diameter of the end of the pipe 30 is enlarged, and therefore the pipe is fixed to the flange member 32.
In recent years, however, various devices are mounted in an engine compartment. Thus, a space for each device is limited. Especially, for providing a space for and around a refrigerating cycle, it has been required to reduce the size of the air conditioning unit. In the above connecting method, however, a jig for supporting the pipe 30 is used to connect the pipe. Thus, a space for the jig is also required. Further, in the above connecting structure, the pipe 30 extends straightly from the fixing base portion 31. Thus, the connecting structure needs a large space for the pipe 30 around the refrigerating device. Accordingly, it is difficult to connect the pipe to the refrigerating device in a small space.